An input/output (I/O) device such as a network interface card (NIC) may couple to a computing platform or host device deployed in server-network edge where the server domain ends and an external network domain begins. A known way to implement switch logic or circuitry at a NIC in these types of environments is through use of a set of lookup tables. The lookup tables may identify a portion of data such as a packet header and then actions may be defined in the lookup table based on the packet header. Lookup tables typically work well in a NIC implementing switch circuitry that connects all the ports via a single switch instance.
A proposed standard by the Institute of Electrical and Electronics Engineers (IEEE) describes implementing numerous switches as part of Edge Virtual Bridging (EVB). The proposed standard has the title of “IEEE Standard for Local and Metropolitan Area Networks—Virtual Bridged Local Area Networks—Amendment Edge Virtual Bridging” and identified as IEEE 802.1Qbg, draft 2.1, published Jan. 30, 2012 (hereinafter “IEEE 802.1Qbg”). A NIC operating in accordance with IEEE 802.Qbg may need to implement separate dedicated switch instances for each logical or virtual port associated with an Ethernet port. Also, the NIC may need to implement additional local switch instances for internal traffic between processing elements at a host device that may include virtual machines (VMs). Further, cascaded switch instances may be needed to implement a Virtual Ethernet Bridge (VEB) or a Virtual Ethernet Port Aggregator (VEPA) within a single Ethernet port. For these multiple switch instances using separate lookup tables for each switch instance may require a substantial amount of NIC resources.